My tranny was shifting hard and on cool mornings would not go into drive instantly. I bought a filter kit and atf+4 fluid and changed both. Now my car shift smooth like a luxury car. I didn't realize that a simple fluid/filter change would make such a drastic difference. If your tranny is hitting hard when it shifts, change the fluid/filter and you will be surprised. Make sure you use atf+4.

 

+1 on that.